2026 Section 163(j) Planning: Business Interest Limits After the EBITDA Addback Returns

For businesses carrying acquisition debt, expansion debt, related-party notes, or working-capital facilities, the tax value of interest expense is not automatic. Section 163(j) can limit the current deduction for business interest expense and push the excess into a carryforward. That matters directly to cash taxes, covenant forecasting, deal models, and owner distributions.

As of July 4, 2026, the rule is more favorable than it was during the 2022 through 2024 EBIT years because the One, Big, Beautiful Bill, P.L. 119-21, restored the addback for depreciation, amortization, and depletion when calculating adjusted taxable income. But the relief is not a free pass. The limitation still has to be modeled on Form 8990, the small-business exception is tested under Section 448(c), and 2026 introduces coordination rules for interest capitalization that can change the timing of deductions.

What Changed for 2026

The major federal change is the return of a tax EBITDA-style ATI calculation. For tax years beginning after December 31, 2024, Section 163(j) allows depreciation, amortization, and depletion deductions to be added back when computing ATI. This increases the interest deduction ceiling for capital-intensive businesses, acquisition-backed companies with amortizable intangibles, manufacturers, software companies with acquired IP, and real estate-adjacent operating businesses that did not elect out.

Calendar-year taxpayers also need to account for the rules effective for tax years beginning after December 31, 2025. IRS FAQs state that Section 163(j) is applied before most mandatory or elective interest capitalization provisions, except Sections 263(g) and 263A(f). The same IRS update also notes that certain CFC income inclusion items are excluded from ATI for tax years beginning after December 31, 2025. Companies with international inclusions, capitalized interest, or long production-period assets should not assume last year's Form 8990 workpaper rolls forward cleanly.

Who Is Still Subject to the Limit

The limitation generally applies to taxpayers with business interest expense unless an exception applies. The most common exception is the small-business exemption: a taxpayer that is not a tax shelter and meets the Section 448(c) gross receipts test. For tax years beginning in 2026, Rev. Proc. 2025-32 sets that gross receipts amount at $32 million based on the average annual gross receipts for the three-tax-year period ending with the preceding tax year.

The trap is aggregation. Related entities may have to combine gross receipts under the Section 448(c)(2), Section 52, and Section 414 rules. A founder with multiple operating companies, a private-equity platform with add-on acquisitions, or a family-owned group that split legal entities by location may not qualify simply because each single EIN is below $32 million.

The Form 8990 Calculation

The basic decision framework is straightforward, but the inputs are not. Start with the taxpayer's business interest expense. Then calculate the limitation as:

1. Business interest income for the taxable year, plus
2. 30% of adjusted taxable income, plus
3. Floor plan financing interest expense, if applicable.

Any business interest expense above that amount is generally disallowed for the current year and carried forward. For a C corporation, this can change taxable income, estimated payments, deferred tax accounting, and lender reporting. For pass-through owners, it can change K-1 economics and the timing of deductions at the partner or shareholder level.

Pass-Through and Deal-Model Traps

Partnerships apply Section 163(j) at the partnership level. Disallowed partnership interest becomes excess business interest expense, or EBIE, allocated to partners. A partner generally cannot use that EBIE until a later year when the same partnership allocates excess taxable income or excess business interest income. That is a very different cash-flow result from a simple partner-level interest carryforward.

S corporations apply the limitation at the S corporation level, and disallowed interest generally carries over at the entity level. For acquisitions, recapitalizations, or capital raises, the tax model should show entity-level interest, partner EBIE, excess taxable income, basis effects, and expected release timing. Buyers and investors should ask for the Form 8990 history, not just an EBITDA schedule from the quality-of-earnings package.

Real Property Election Tradeoff

Eligible real property trades or businesses and farming businesses may elect to be excepted from Section 163(j). That can be valuable when leverage is high and interest deductibility is more important than accelerated depreciation. But the real property election has a cost: affected nonresidential real property, residential rental property, and qualified improvement property must generally use the alternative depreciation system and are not eligible for bonus depreciation.

That tradeoff changed after the EBITDA addback returned. Some businesses that previously considered electing out may now have enough ATI capacity without giving up bonus depreciation. Others may still benefit from the election because interest expense is structurally higher than depreciation benefits. The analysis should compare current and projected Form 8990 results against ADS lives, bonus depreciation, state rules, and exit timing.

What the Workpaper Should Show

A defensible 2026 Section 163(j) file should include more than a single Form 8990 output. It should reconcile book interest to tax business interest, identify excepted and non-excepted activities, document the Section 448(c) gross receipts test, apply aggregation rules, compute ATI, track carryforwards, and explain pass-through excess items. Companies with international operations should separately flag CFC inclusions and the 2026 ATI changes.

The workpaper should also connect to planning decisions. If management is choosing between refinancing, purchasing equipment, accelerating bonus depreciation, making a real property election, or closing an acquisition before year-end, the model should show the after-tax interest capacity in each scenario.

Common Mistakes

• Using bank EBITDA as tax ATI. Lender EBITDA and Section 163(j) ATI are not the same calculation.
• Skipping the gross receipts aggregation test. Related entities can push an otherwise small taxpayer above the $32 million threshold.
• Assuming the EBITDA addback solves everything. The addback raises capacity, but it does not automatically make all interest deductible.
• Ignoring EBIE mechanics. Partnership excess business interest expense can be trapped until future excess taxable income or interest income from the same partnership.
• Making an electing real property trade or business election without modeling ADS. The election can protect interest deductions while sacrificing bonus depreciation and shorter recovery benefits.
• Forgetting state conformity. State returns may require addbacks, separate calculations, or different carryforward tracking.

The Bottom Line

The 2026 Section 163(j) rules are more favorable for many leveraged companies, but they are still technical enough to change cash taxes materially. The right planning file should prove whether the taxpayer is exempt, compute Form 8990 under the new ATI rules, track carryforwards and EBIE, evaluate real property election tradeoffs, and identify state conformity differences before management relies on interest deductions in a budget, deal model, or distribution plan.